Proximal femoral osteotomy (PFO) is a widely performed reconstructive surgery in children with neurologic hips. Asymmetric muscle forces produced across the hip are responsible for the development of hip deformities, such as coxa valga, persistent femoral anteversion, acetabular dysplasia, windswept deformity, and pelvic obliquity. Incidence of these hip deformities varies with the severity of the disease, and may lead to hip dislocation in more than 75% of severe spastic quadriplegic patients as reported in Khouri et at. Entitled “Proximal Femoral Osteotomy in Neurologic Pediatric hips Using the Locking Compression Plate (J Pediatric Orthopedic 2010; 30:825-831.
Other deformities of the proximal hip include developmental coxa vara and hinge abduction. Valgus subtrochanteric osteotomy is the current gold standard for treatment of coxa vara, while treatment of hinge abduction is also done through valgus osteotomy in children with severely involved Legg-Calvé-Perthes disease.
PFO has been shown to have a significant role in correcting these acquired deformities. Many implants have been used for the fixation of PFOs. With the development of the association for osteosynthesis instrumentation, the single-piece 90 degrees fixed-angle blade plate has come to be widely used. Other pediatric instrumentation have also been developed using a two-piece sliding hip screw (Richards intermediate hip screw) with the insertion of the sliding screw in the center of the femoral neck. Later devices consist of a screw-plate implant or blade-plate implant with insertion of an “antirotation screw” for engaging the proximal fragment and providing enhanced antirotation fixation. These types of devices have shown more successful fixation; however, discomfort, bursitis, and even skin breakdown with the exposure of the underlying plate can occur due to the bulkiness of these types of implants. Position change of the proximal fragment and loss of fixation have also been observed in some osteoporotic patients.
As such, there is a need for a blade-plate device that simplifies the surgical technique via a chisel-free modular system and creates a biomechanically correct lateralization or medicalization of the femoral shaft depending on the type of osteotomy being performed.